On construction sites, explosives are commonly used for altering the terrain and for demolition purposes. Construction grade explosives are most often used as several smaller charges placed in drilled holes in the rock or construction to be blasted. The charges are electrically connected to a detonator and are detonated simultaneously or in a synchronized pattern. Due to the large amount of charges, there is always a risk of one or more charges failing, which could be a result of a problem with the explosives or with the electrical connection with the detonator. When an excavator or similar heavy machinery works in the rockfill, the risk of the excavator accidentally squeezing or hitting a dud with enough force to cause it to detonate is quite substantial. Exploding duds creates a blast shock wave against the excavator and rockfill or other matter may be thrown against the excavator at speeds similar to that of a speeding bullet.